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Operations, R "7. operations – Alpha Technologies 255A Bypass Switch User Manual

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0200018-J0 Rev C

7.  Operations

1. To allow manual transfer, turn the lockout-key to IN PHASE BYPASS ENABLE

The NORMAL/ BYPASS switch position cannot be changed if power is not present from

either power source. The Alpha MBS operates normally if at least one power source is

present. See Table A.

CAUTION!

The MANUAL OVERRIDE key can be used to change the source selection of the Alpha

MBS even when the inputs are out-of-phase condition. Operating with the inputs out of

phase could cause damage to the critical loads.

CAUTION!

2. When the green IN PHASE lamp is illuminated, turn the

switch on the side panel (Figure 8) to BYPASS.

3. Turn the lockout-key to LOCKED to prevent inadvertent

transfer.

Electro-mechanical

key-operated switch

IN PHASE lamp

Figure 9 — Side panel NORMAL/BYPASS switch

Figure 8 — In phase bypass enable

Refer to section 3.3 to lockout the manual switch with a padlock.

NOTE: